<!--
 * @Author: 高瑞寒 15932717091@163.com
 * @Date: 2022-04-25 21:35:52
 * @LastEditTime: 2022-04-25 21:54:04
 * @LastEditors: 高瑞寒 15932717091@163.com
 * @Description: 1_钩子函数
-->
<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>1_钩子函数</title>

</head>

<body>
  <div id="test"></div>
  <script type="text/javascript" src="../js/react.development.js"></script>
  <script type="text/javascript" src="../js/react-dom.development.js"></script>
  <script type="text/javascript" src="../js/babel.min.js">
  </script>
  <script src="../js/prop-types.js"></script>
  <script type="text/babel">
    class Life extends React.Component {
      state = { opacity: 1 }
      unmounted = () => {
        ReactDOM.unmountComponentAtNode(document.querySelector('#test'))
      }
      componentDidMount() {
        this.timer = setInterval(() => {
          let { opacity } = this.state
          opacity -= 0.1
          this.setState({ opacity })
          if (opacity < 0) {
            this.setState({ opacity: 1 })
          }
        }, 200)
      }
      componentWillUnmount(){
        clearInterval(this.timer)
      }
      render() {
        return (
          <div>
            <h1 style={{ opacity: this.state.opacity }}>Hello world</h1>
            <button onClick={this.unmounted}>消失</button>
          </div>
        )
      }
    }
    ReactDOM.render(<div><Life /></div>, document.querySelector('#test'))
  </script>
</body>

</html>